Yep...clutches don't grind unless there's no fibers left, in which case it would never move and it would grind all the time. My guess is that either you didn't get something right in the transmission or it's in the final drive. I believe this is a shaft drive (but could be wrong)...I'd look there first. Power brake it and see if either of the drive shafts are spinning. If it is, then my guess is that you have a worn out gearbox. I'm not sure how the internals are set up on these, but it could be a bad bearing that's allowing too much gear lash or a bad gear itself. Further forward and it could be a bad cv axle.